JPS62241711A - Tread part structure of pneumatic tire - Google Patents

Abstract

PURPOSE:To improve the properties of braking and cornering by forming the sipings extending in the tire axial and peripheral directions onto the surfaces of the center block and side block which are formed on the tread part and divided by grooves. CONSTITUTION:As for a pneumatic tire 1, the first longitudinal groove 8 positioned on the equator 6 and the second longitudinal grooves 9 positioned on the right and left sides are formed in the tire peripheral direction on the tread part 2. Each longitudinal groove 7, 9 is formed from each aslant groove part 10, 11 inclined with respect to the tire peripheral and tire axial directions and each lateral groove part 12, 13 formed in the tire axial direction. A center block 15 is formed from the both both lateral grooves 8 and 9 and a lateral connecting groove 14, and a side block 17 is formed from the second lateral groove 9 and a side lateral groove 16. In this case, the sipings 21 and 22 extending in the tire axial direction are formed on the center block 15, and the sipings 23 and 24 extending in the tire peripheral direction are formed on the side block 17.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to the structure of a tread portion of a pneumatic tire.

(Prior art) Winter tires include spike tires with spike pins and so-called studless tires without spike pins, but spike tires have better traction on compacted snow and frozen roads in winter. It has excellent braking, cornering, and pitching performance.

Incidentally, in recent years, dust pollution caused by abrasion dust from the spike pins of spiked tires has become a problem, and regulations on the use of spiked tires are being considered.

Therefore, there is a demand for making the performance of studless tires as close as possible to that of spiked tires, so that even studless tires can exhibit good performance on compacted snow and frozen roads in winter.

In order to improve the performance of studless tires, there are two methods: improving the material of the trend part and improving the structure of the tread part.

By the way, the structure of the tread portion is generally configured as follows. That is, a large number of blocks surrounded by grooves are arranged in the tread portion, and sipes are formed in each block.

(Problem to be solved by the invention) However, in the above-mentioned conventional methods, little consideration has been given to how to form siping in order to improve traction, braking, cornering, and hill climbing performance. Improvements in this regard are desired.

The present invention provides a pneumatic tire that can solve the above problems.
The purpose is to provide the structure of the Leso IS section.

(Means for solving the problems) In order to achieve the above object, the features of the present invention are as follows:
In the tread part, a large number of blocks surrounded by grooves are arranged, and siping is formed on each block, and each block has both siping approximately in the circumferential direction of the tire and siping approximately in the axial direction of the tire. At the point.

(Embodiment) Hereinafter, a first embodiment of the present invention will be explained based on the drawings of FIGS. 1 to 3. FIG. 2. Shoulder part 3
, a sidewall part and a bead part, and the overall shape is a toroidal shape. 4 is carcass ply, 5
is Tresotov.

It's Rai.

FIG. 1 is a plan view of the tread portion 2, where 6 is the equator located at the center of the trend portion 2 in the axial direction of the tire, and 7 is the side edge of the tread portion 2.

The trend portion 2 includes a first vertical groove 8 located on the equator 6;
The 211th grooves 9 located on both the left and right sides are formed in a zigzag shape in the tire circumferential direction.

Each of the first and second longitudinal grooves 8 and 9 has an inclined groove portion 10° 11 that is inclined with respect to both the tire circumferential direction and the tire axial direction, and a substantially tire axial direction (including the tire axial direction. When referring to the tire axial direction and the tire circumferential direction, the tire axial direction and the tire circumferential direction are also included, respectively). 12 and 13 are arranged alternately in the tire circumferential direction.

The pitch of the first longitudinal grooves 8 is twice the pinch of each second longitudinal groove 9, and the left and right second longitudinal grooves 9 are shifted by half a pitch in the tire circumferential direction. Two pitches correspond to one pitch of each second longitudinal groove 9 in the tire circumferential direction.

Although the respective inclined groove portions 11 of the left and right second longitudinal grooves 9 are parallel, the inclined groove portions 10 of the first longitudinal groove 8 and the inclined groove portions 11 of the second!1 groove 9 are arranged as follows toward one side in the tire circumferential direction. It has an inclined shape that moves in opposite directions with respect to the tire axial direction.

Each inclination angle θ1. of the inclined groove portions io, 1i of each vertical groove 8.9 with respect to the tire circumferential direction. θ2 is in the range of 10° to 60″, the inclination angle θ1 is preferably 25°, and the inclination angle θ2 is preferably 21″.

As shown in FIG. 3, the cross section of each vertical groove 8.9 is V-shaped with an arcuate bottom, and the angle θ3 formed by each side wall with the groove depth direction is about 10°.

Each lateral groove part 12 of the first longitudinal groove 8 is connected to each corresponding lateral groove part 13 of the left and right second longitudinal grooves 9 via a communication lateral groove 14 formed approximately in the tire axial direction, and the tread part 2 At the axial center of the tire, a large number of center blocks 15 surrounded by first and second longitudinal grooves 8.9 and connecting lateral grooves 14 are arranged in two rows in the tire circumferential direction.

Side lateral grooves 16 are formed approximately in the axial direction of the tire from the longitudinal center portions of the inclined groove portions 11 of the left and right second vertical grooves 9, and are open outwardly, and extend from both sides of the tread portion 2 in the tire axial direction. A large number of side blocks 17 in a row surrounded by second longitudinal grooves 9 and side lateral grooves 16 are arranged in the tire circumferential direction. The cross-sectional shapes of the communication lateral grooves 14 and the side lateral grooves 16 are also formed as shown in FIG. 3.

Siping 21. is formed approximately in the axial direction of the tire on the inner side in the tire axial direction of the side blocks 15 and 17 in the central portion.
22 are arranged in several rows in the tire circumferential direction, and sipes 23.
24 are arranged in several rows in the axial direction of the tire.

The left and right sides of the tread portion 2 across the equator 6 have the same shape, differing only in direction with respect to the tire circumferential direction.

According to the first embodiment configured as described above, when driving on a compressed snow road surface, frozen road surface, etc., the first and second
Horizontal groove portion 12.13 and inclined groove portion 10.
The opening edges, side walls, etc. of No. 11 have a digging effect or a digging effect on the compacted snow road surface, frozen road surface, etc.
As a result, the lateral groove portion 12. which is formed approximately in the tire axial direction.
13, it is possible to greatly improve the slip resistance in the front and back of the running direction, and the inclined grooves 10 and 11 formed in an inclined shape in the circumferential direction of the tire can also improve the slip resistance in the front and back of the running direction. braking,
You can improve your pitching performance.

Therefore, there is no need to increase the jig-jig width of the first and second longitudinal grooves 8.9 in order to improve each of the above-mentioned performances as in the past, and there is no need to increase the jig-jig width of each of the first and second vertical grooves 8.9, which may lead to deterioration of wet performance or quietness performance. do not have.

In addition, sipes 2 are formed approximately in the axial direction of the tire on the inner side of each center/side block 15.17 in the axial direction of the tire.
1.22 are arranged in parallel in the circumferential direction of the tire, the opening edges and side walls of these sipes 21.22 have a digging and digging effect on the compacted snow road surface, frozen road surface, etc., so that the sipes 21. It can improve resistance to IH, and improve traction, braking, and pitching performance.

Further, since several sipes 23.24 formed substantially in the tire circumferential direction are arranged in parallel in the tire axial direction on the outer side in the tire axial direction of each center/side block 15.17,
The opening edges and side walls of these sipes 23 and 24 have a digging or digging effect on the compressed snow road surface, frozen road surface, etc., so that the slip resistance in the axial direction of the tire can be improved and the cornering performance can be improved.

FIG. 4 shows a second embodiment of the present invention, in which the first vertical groove 8
There are two grooves, and the corresponding lateral grooves 12 of the left and right first vertical grooves 8
are connected by a communication lateral groove 26 formed approximately in the tire axial direction, and a center block 27 surrounded by the brush 1 longitudinal groove 8 and the communication lateral groove 26 is located at the center of the tread portion 2 in the tire axial direction. A large number of them are arranged in the circumferential direction. And, on the side of the center block 27 in the tire axial direction,
On the other side, several sipes 58 formed substantially in the tire axial direction are arranged in parallel in the tire circumferential direction, and on the other side, several sipes 59 formed substantially in the tire circumferential direction are arranged in parallel in the tire axial direction. There is. In the adjacent central blocks 27, the sipes 58 and 59 are formed on opposite sides in the tire axial direction.

FIG. 5 shows a third embodiment of the present invention, in which two 2nd!1 grooves 9 are provided on each left and right side in the tire axial direction of the tread portion 2, and two second! Vertical groove 9
The corresponding lateral grooves 13 are connected by a connecting lateral groove 30 formed approximately in the axial direction of the tire, and the second longitudinal groove 9 and the connecting lateral groove 30 are formed on each left and right side of the tread portion 2 in the tire axial direction.
A large number of central blocks 31 are arranged in the circumferential direction of the tire. On the inner side of the center block 31 in the tire axial direction, several sipes 61 extending approximately in the tire circumferential direction are arranged in parallel in the tire circumferential direction, and on the outer side of the tire axial direction, sipings 62 extending approximately in the tire circumferential direction are arranged in parallel in the tire circumferential direction. Several rows are arranged in parallel in the axial direction.

6 and 7 show a fourth embodiment of the present invention,
Each communication lateral groove 14 and each side lateral groove 16 are divided into two parts having the same length or substantially the same length in the tire axial direction, and are composed of an inner groove part 34.35 and an outer groove part 36.37.

As shown in FIG. 7, the inner groove portions 34, 35 are arranged in the groove depth direction so that the center line 39 in the width direction of the groove section cross-section moves toward the width direction of each lateral groove 14, 16 toward the groove bottom. 40, and the outer groove portions 36.37 are inclined in the groove depth direction 40 so that the center line 41 in the width direction of the groove tank cross section moves to the other side in the width direction of each lateral groove 14.16 as it moves toward the groove bottom. tilted against.

Then, as shown by the imaginary lines in FIG.
7, the maximum angle θ4 formed between the side wall portion on the side where the center line 39.41 moves toward the groove bottom and the groove depth direction 40 is On the other hand, the angle θ4 is preferably set to 0°.

Further, the angle θ5 formed by the other side wall of each of the grooves 34 to 37 and the groove depth direction 40 is in the range of 10 to 30°, and preferably the angle θS is 15°.

According to the embodiment configured as described above, each communication lateral groove 14
When the side horizontal grooves 16 touch the ground, these inner grooves 3
4.35 and the outer grooves 36, 37 open diagonally downward in the forward direction of travel, and the other opens diagonally downward in the rear direction in the travel direction, so the opening edges of these grooves 34 to 37 and Due to the good digging and digging action of the side walls and the like on the compacted snow and frozen road surfaces, the slip resistance of the tire 1 in the longitudinal direction of travel can be increased, and traction, braking, and climbing performance can be improved.

In addition, as shown by the imaginary line in FIG. 6, each of the first and second vertical grooves 8
, 9 are also divided into two parts of the same length or approximately the same length in the elongated direction to form a front groove part (the upper side is the front side in FIG. 6) 43.44 and a rear groove part 45°. 46, and the center line in the width direction of the groove cross section of the front groove part 43.44 and the center line in the width direction of the groove groove cross section of the rear groove part 45.46 are defined by the inner groove part 34.46.
35 or the outer groove portions 36, 37, it may be inclined with respect to the groove depth direction.

If each inclined groove part 10.11 of each of the first and second longitudinal grooves 8.9 is configured as described above, since the inclined groove part 10.11 is inclined in both the tire circumferential direction and the tire axial direction,
The opening edges and side walls of the front groove portions 43, 44 and the outer groove portions 45, 46 have good digging and digging effects on compacted snow and frozen road surfaces, which improves the tire 1's slip resistance in the running direction. It is possible to improve the slip resistance of the tire l in the left and right directions in the tire axial direction, and it is possible to improve each performance of traction, braking, hill climbing, and cornering.

In addition, as shown by the imaginary lines in FIG.
．． 11 etc. in the longitudinal direction from the first to third grooves 48°49,5
Divide into 3 to 4 or more parts to 0, and divide the above divided parts into 1
In some cases, the inner groove portions 34 and 35 are formed separately, and the other divided portions are formed as outer groove portions 36 and 37.

Furthermore, as described above, the direction of inclination of the center line in the width direction of the cross section of the groove tank may not be changed all at once, but the direction of inclination of the center line may be changed gradually.

8 to 11 show a fifth embodiment of the present invention, in which the sipes 21 of each center and side block 15.
．． 22 is formed in a straight line, and each siping 21, 22
Siping 21.22 is placed on the axially outer side end of the tire.
A first hole 52.55 is formed in the shape of a round hole in the depth direction reaching the bottom from the opening on the ground surface side of each sipe 2.
At the bottom of the siping 21.22, there is a second round hole extending in the longitudinal direction of the sipe 21.22, communicating with the first hole 52.55, and opening into each of the first and second vertical *8.9 holes. Hole 53.56
is formed.

Also, the siping 2 of each center/side block 15.17
3.24 is formed in a straight line in the circumferential direction of each block 15.17, extending from the side to the other side, and similarly to the above,
A first hole 52 is provided at the other end in the circumferential direction of the sipes 23 and 24.
．． 55 is formed, and a second hole 53.56 is formed at the bottom of the siping 23.24.

According to the fifth embodiment configured as described above, the first and second holes 5 are provided in the sipes 21 to 24 of each block 15.17.
2.55, 53.56 respectively, so when each block 15.17 is grounded, each block 15°17
As shown in FIG. 11, the sipes 21 to 24 of the sipes 21 to 24 can be easily opened widely, and thereby the opening edges and side walls of the sipes 21 to 24 have good digging and digging effects on the compacted snow road surface, frozen road surface, etc. This improves the traction, braking, cornering, and pitching performance of Tire 1.

Also 1. When driving on a compacted snow or frozen road surface with a temperature around θ°C, there is a film of water from melted snow or ice between the grounded block 15.17 and the road surface, but the grounded block 15. The sipings 21 to 24 of No. 17 are wide open as described above (so the water interposed between the block 15.17 and the road surface is absorbed by the sipes 21 to 24, the first and second holes 52.
．． The second vertical groove 9 and the side horizontal groove 16 are well formed through 53 and 56.
discharged inside.

Therefore, the frictional force of the tire 1 can be increased even at around 0° C., and each performance of traction, braking, cornering, and hill climbing can be improved.

In addition, as shown by the imaginary line in FIG.
24 and the second holes 53 and 56 may be formed over the entire length of each center block 15 and side block 17 in the tire axial direction or tire circumferential direction.

FIG. 12 shows a sixth embodiment of the present invention, in which the sipes 21 to 24 on each block 15, 17 are formed opposite to the first embodiment with respect to the tire axial direction.

FIG. 13 shows a seventh embodiment of the present invention, in which vertical grooves 58
The pattern of the tread portion 2 is significantly different from the above embodiments, such as that the tread portions are straight. and central block 1
Several sipes 21 extending approximately in the axial direction of the tire are arranged in parallel in the tire circumferential direction at the center of the tire 5, and several sipings 23 extending substantially in the tire circumferential direction are arranged in parallel in the axial direction on both sides of the tire axial direction. has been done.

Note that the above embodiments may be freely combined.

Incidentally, in the embodiment, siping is appropriately omitted.

(Effects of the Invention) As detailed above, according to the present invention, traction,
Performance such as braking, cornering, and pitching can be improved. The present invention has the above advantages and is of great practical benefit.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a partial plan view of the 1-red portion, FIG. 2 is a partial cross-sectional view of the tie-1, and FIG. 1 is a cross-sectional view taken along the line A-A in FIG. The figure shows a fourth embodiment of the present invention, and FIG. 6 is a partial plan view of the tread portion.
Figure 7 is a sectional view taken along the line B-B in Figure 6, and Figures 8 to 1.
1 shows a fifth embodiment of the present invention, FIG. 8 is a partial plan view of the tread portion, and FIG. 9 is a cross-sectional view taken along the line CC in FIG.
Fig. 10 is a perspective sectional view of the main part, Fig. 11 is a partial plan view of the container for explaining the operation, and Figs. 12 and 13 show the sixth and seventh embodiments of the present invention. (This is a partial plan view of the red part. 1... Pneumatic tire, 2... Trend part, 8, 9
...First and second vertical grooves, 14.26.30...Connecting horizontal grooves, 15.27°31...Central block, 16...
・Side horizontal groove, I7...Side block, 21-24.5
8.59.61.62...Siping.

Claims (1)

[Claims] (1) In a tread section in which a large number of blocks surrounded by grooves are arranged and siping is formed on each block, each block has both siping in the circumferential direction of the tire and siping in the axial direction of the tire. A structure of a tread portion of a pneumatic tire characterized by forming.